JPH07190863A - Temperature sensor - Google Patents
Temperature sensorInfo
- Publication number
- JPH07190863A JPH07190863A JP5329306A JP32930693A JPH07190863A JP H07190863 A JPH07190863 A JP H07190863A JP 5329306 A JP5329306 A JP 5329306A JP 32930693 A JP32930693 A JP 32930693A JP H07190863 A JPH07190863 A JP H07190863A
- Authority
- JP
- Japan
- Prior art keywords
- resistor
- voltage
- ceramic substrate
- voltage dividing
- temperature sensor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K15/00—Testing or calibrating of thermometers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K13/00—Thermometers specially adapted for specific purposes
- G01K13/02—Thermometers specially adapted for specific purposes for measuring temperature of moving fluids or granular materials capable of flow
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
- G01K7/16—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements
- G01K7/18—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer
- G01K7/183—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer characterised by the use of the resistive element
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K2205/00—Application of thermometers in motors, e.g. of a vehicle
- G01K2205/04—Application of thermometers in motors, e.g. of a vehicle for measuring exhaust gas temperature
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Thermistors And Varistors (AREA)
- Measuring Temperature Or Quantity Of Heat (AREA)
- Apparatuses And Processes For Manufacturing Resistors (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】 本発明は、白金又は白金とセラ
ミックとのサーメットを抵抗体として用いた温度センサ
に関し、精度が高く、高温での信頼性が高い温度センサ
を提供する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensor using platinum or a cermet of platinum and ceramics as a resistor, and provides a temperature sensor having high accuracy and high reliability at high temperatures.
【０００２】[0002]
【従来の技術】 従来より、セラミック基体に白金抵抗
体を設け、この抵抗体をレーザーでトリミングして所定
の抵抗値とし、抵抗体上にガラスを被覆した温度センサ
が知られている（特開平４−２７９８３１号公報）。2. Description of the Related Art Heretofore, there has been known a temperature sensor in which a platinum resistor is provided on a ceramic substrate, the resistor is trimmed with a laser to have a predetermined resistance value, and the resistor is covered with glass (Japanese Patent Application Laid-Open No. Hei 10 (1999) -242242). 4-27983).
【０００３】[0003]
【発明が解決しようとする課題】しかし、抵抗体がレー
ザー照射を受けてトリミングされる工程において、抵抗
体の温度が上昇するが、抵抗体の抵抗温度係数が大きい
ため、抵抗体の抵抗値の精度を高くすることが難しく、
個々の温度センサの抵抗値はバラツキが大きくなる場合
があった。また、抵抗体を被覆するガラス被覆層は耐熱
性が限られているので、高温で温度センサを使用できな
い場合があった。However, although the temperature of the resistor rises in the process of trimming the resistor by laser irradiation, the resistance temperature coefficient of the resistor is large, so that the resistance value of the resistor is It is difficult to increase the accuracy,
The resistance value of each temperature sensor may vary greatly. Further, since the glass coating layer that covers the resistor has a limited heat resistance, the temperature sensor may not be used at high temperatures.
【０００４】 また、温度センサは、その用途によっ
て、高温で又は酸化若しくは還元雰囲気中で用いられる
ことがある。更に、温度センサは、自動車の排気ガス、
工場の排気ガス等の腐食性ガスを含む雰囲気で用いられ
ることもある。温度センサの抵抗体は、これらの雰囲気
で劣化し、抵抗値が経時変化する場合があった。Further, the temperature sensor may be used at a high temperature or in an oxidizing or reducing atmosphere depending on its application. In addition, the temperature sensor is
It may be used in an atmosphere containing corrosive gas such as exhaust gas from a factory. The resistor of the temperature sensor may be deteriorated in these atmospheres and the resistance value may change with time.
【０００５】[0005]
【課題を解決するための手段】 そこで、本発明は、こ
れらの上記の課題を解決することを目的とする。即ち、
本発明によれば、セラミック基体と、該セラミック基体
に埋没され、かつ、正の抵抗温度係数を有する抵抗体
と、該抵抗体に電流を印加するための電流リードと、該
抵抗体の電圧を検出するための電圧リードと、該電圧リ
ード間に発生する電圧を分圧する分圧抵抗体とを有し、
該抵抗体が、金属、合金、又は、金属とセラミックとの
混合物から構成されており、かつ、該抵抗体に所定の電
流を流した際に発生する電圧が所定電圧値となるように
該分圧抵抗体がトリミング調整されていることを特徴と
する温度センサが提供される。本発明において、該分圧
抵抗体は該セラミック基体の表面の少なくとも一部を被
覆することが好ましい。また、該抵抗体が該セラミック
基体の端部に位置し、該分圧抵抗体が該セラミック基体
の他の端部に位置することが好ましい。更に、本発明に
おいて、該分圧抵抗体がガラスで被覆されていることが
好ましい。更にまた、該分圧抵抗体の抵抗値は、該抵抗
体の抵抗値の１００倍以上であることが好ましい。Therefore, an object of the present invention is to solve these problems described above. That is,
According to the present invention, a ceramic substrate, a resistor buried in the ceramic substrate and having a positive temperature coefficient of resistance, a current lead for applying a current to the resistor, and a voltage of the resistor are provided. A voltage lead for detecting, and a voltage dividing resistor for dividing the voltage generated between the voltage leads,
The resistor is composed of a metal, an alloy, or a mixture of metal and ceramic, and the voltage generated when a predetermined current is applied to the resistor has a predetermined voltage value. A temperature sensor is provided in which the piezoresistor is trimmed. In the present invention, the voltage dividing resistor preferably covers at least a part of the surface of the ceramic substrate. Further, it is preferable that the resistor is located at the end of the ceramic base and the voltage dividing resistor is located at the other end of the ceramic base. Further, in the present invention, it is preferable that the voltage dividing resistor is covered with glass. Furthermore, the resistance value of the voltage dividing resistor is preferably 100 times or more the resistance value of the resistor.
【０００６】[0006]
【作用】 本発明の温度センサでは、セラミック基体の
内部に抵抗体が設けられているので、抵抗体が測定雰囲
気に接触することがなく、抵抗体が劣化し難い。従っ
て、高温酸化雰囲気、高温還元雰囲気、腐食性ガスを含
有する雰囲気でも、本発明の温度センサの安定性は高
い。In the temperature sensor of the present invention, since the resistor is provided inside the ceramic substrate, the resistor does not come into contact with the measurement atmosphere, and the resistor is less likely to deteriorate. Therefore, the stability of the temperature sensor of the present invention is high even in a high temperature oxidizing atmosphere, a high temperature reducing atmosphere, or an atmosphere containing a corrosive gas.
【０００７】 セラミック基体に用いるセラミックは、
抵抗体の抵抗値と比較して、電気的に絶縁性であること
が好ましい。また、熱伝導率が小さい方が、温度センサ
の精度を高めるので好ましい。セラミック基体は、例え
ば、アルミナ、ステアタイト、ムライト等を用いること
ができる。セラミック基体は、全体が同一の材料からな
ることが好ましいが、セラミック基体のある部分が他の
部分と異なる材料であってもよい。また、セラミック基
体は、ガス分子が透過しないように、緻密であることが
好ましい。セラミック基体の形状は、板状に限られず、
棒状、パイプ状であってもよい。この形状は、抵抗体で
測定する温度が、分圧抵抗体に影響を及ぼし難い形状、
即ち、熱伝導率が小さくなるような形状が好ましい。The ceramic used for the ceramic substrate is
It is preferably electrically insulating as compared with the resistance value of the resistor. In addition, it is preferable that the thermal conductivity is small because the accuracy of the temperature sensor is improved. As the ceramic substrate, for example, alumina, steatite, mullite or the like can be used. The ceramic substrate is preferably made of the same material as a whole, but one portion of the ceramic substrate may be made of a material different from that of another portion. Further, the ceramic substrate is preferably dense so that gas molecules do not pass through. The shape of the ceramic substrate is not limited to the plate shape,
It may be rod-shaped or pipe-shaped. This shape is such that the temperature measured by the resistor does not easily affect the voltage dividing resistor,
That is, a shape having a small thermal conductivity is preferable.
【０００８】 抵抗体は、正の抵抗温度係数を有する金
属を含有する。この金属として白金、ロジウム、ニッケ
ル、タングステン等を用いることができ、特に白金は好
ましい。抵抗体は、これらの金属又はこれらの金属を含
有する合金とセラミックとのサーメットであってもよ
い。また、抵抗体がこれらの金属の単体又はこれらの金
属を含有する合金であってもよいことはいうまでもな
い。本発明の温度センサは、温度変化によって抵抗体の
抵抗値が変化する特性を利用して、温度を測定するもの
である。The resistor contains a metal having a positive temperature coefficient of resistance. Platinum, rhodium, nickel, tungsten or the like can be used as this metal, and platinum is particularly preferable. The resistor may be a cermet of ceramics with these metals or alloys containing these metals. Needless to say, the resistor may be a simple substance of these metals or an alloy containing these metals. The temperature sensor of the present invention measures the temperature by utilizing the characteristic that the resistance value of the resistor changes with the temperature change.
【０００９】 分圧抵抗体は、抵抗体に電気的に接続す
るものであり、例えば、電流リードを介して抵抗体に接
続する。分圧抵抗体は、抵抗体と異なって、抵抗温度係
数が小さいことが好ましい。分圧抵抗体は、例えば、金
属又は金属酸化物がセラミック基体に印刷付与されたも
の、金属又は金属酸化物の粒子がガラスに分散したも
の、金属又は金属酸化物からなる薄膜、金属細線等を用
いることができる。分圧抵抗体は、セラミック基体の表
面の少なくとも一部を被覆することが好ましく、これに
より、分圧抵抗体をレーザー等でトリミングすることが
でき、抵抗体と分圧抵抗体の全体の抵抗値を調整するこ
とができる。即ち、所定温度（例えば、２５℃）で、抵
抗体に所定の電流を流したときに発生する逆起電力を、
電圧として検出しながら、分圧抵抗体をレーザーでトリ
ミングすることで、分圧抵抗体の抵抗値を調整すること
ができる。従って、個々の温度センサの抵抗値のバラツ
キが低減される。The voltage dividing resistor is electrically connected to the resistor, and is connected to the resistor via a current lead, for example. Unlike the resistor, the voltage dividing resistor preferably has a small temperature coefficient of resistance. The voltage dividing resistor may be, for example, one in which a metal or a metal oxide is printed on a ceramic substrate, one in which particles of a metal or a metal oxide are dispersed in glass, a thin film made of a metal or a metal oxide, a fine metal wire, or the like. Can be used. The voltage dividing resistor preferably covers at least a part of the surface of the ceramic substrate, whereby the voltage dividing resistor can be trimmed with a laser or the like, and the total resistance value of the resistor and the voltage dividing resistor is Can be adjusted. That is, the counter electromotive force generated when a predetermined current is passed through the resistor at a predetermined temperature (for example, 25 ° C.) is
The resistance value of the voltage dividing resistor can be adjusted by trimming the voltage dividing resistor with a laser while detecting the voltage. Therefore, the variation in the resistance value of each temperature sensor is reduced.
【００１０】 また、分圧抵抗体は、抵抗体よりも抵抗
温度係数が小さいので、レーザで分圧抵抗体をトリミン
グすることを、レーザーで抵抗体をトリミングすること
と比較すると、レーザー照射を受ける分圧抵抗体に発生
する熱に起因する分圧抵抗体の抵抗値の誤差が小さくな
る。更に、抵抗体の逆起電力を測定しながらレーザーで
分圧抵抗体をトリミングするため、電流リード、電圧検
出リードの温度変化による抵抗変化は無視できるように
なり、抵抗体及び分圧抵抗体の抵抗値のバラツキが小さ
くなる。更にまた、分圧抵抗体は、温度を測定する雰囲
気には接触しない部位に配置できるので、分圧抵抗体が
劣化し難くなり、分圧抵抗体は抵抗値が経時変化し難
い。Further, since the voltage dividing resistor has a smaller temperature coefficient of resistance than the resistor, trimming the voltage dividing resistor with a laser is irradiated with laser as compared with trimming the resistor with a laser. The error in the resistance value of the voltage dividing resistor due to the heat generated in the voltage dividing resistor is reduced. Further, since the voltage dividing resistor is trimmed by the laser while measuring the counter electromotive force of the resistor, the resistance change due to the temperature change of the current lead and the voltage detecting lead can be ignored, and the resistor and the voltage dividing resistor are Variations in resistance are reduced. Furthermore, since the voltage dividing resistor can be arranged in a portion that does not come into contact with the atmosphere for measuring temperature, the voltage dividing resistor is less likely to deteriorate, and the resistance value of the voltage dividing resistor is less likely to change with time.
【００１１】 分圧抵抗体の抵抗値は、温度センサの精
度を高めるために、抵抗体の抵抗値の１００倍以上であ
ることが好ましく、１０００倍以上であることは更に好
ましい。また、温度を測定する環境又は抵抗体からの伝
熱を避けるため、分圧抵抗体は、抵抗体からある程度離
れた位置に配置することが好ましい。例えば、抵抗体
は、セラミック基体の端部に配置し、分圧抵抗体は、セ
ラミック基体の他の端部に配置することが好ましい。In order to improve the accuracy of the temperature sensor, the resistance value of the voltage dividing resistor is preferably 100 times or more, more preferably 1000 times or more the resistance value of the resistor. Further, in order to avoid heat transfer from the environment for measuring the temperature or the resistor, it is preferable to dispose the voltage dividing resistor at a position apart from the resistor to some extent. For example, it is preferable that the resistor is arranged at the end of the ceramic base and the voltage dividing resistor is arranged at the other end of the ceramic base.
【００１２】 また、分圧抵抗体は、耐久性を向上させ
るため、ガラスで被覆されていることが好ましい。温度
センサで高温を測定するときであっても、分圧抵抗体
は、その高温の影響を被り難い部位に配置できるので、
分圧抵抗体のガラス被覆層は、十分に耐久性を保つこと
ができる。ガラスで被覆する方法は、例えば、ホウケイ
酸鉛ガラス等のガラス粉末をスラリーとし、このスラリ
ーを浸漬、ブレード塗布、スプレー塗布等によって分圧
抵抗体の表面に付着させ、この表面に付着しているスラ
リーを乾燥させ、次いで、焼成することが挙げられる。Further, the voltage dividing resistor is preferably covered with glass in order to improve durability. Even when measuring a high temperature with a temperature sensor, the voltage divider resistor can be placed in a portion that is unlikely to be affected by the high temperature.
The glass coating layer of the voltage dividing resistor can sufficiently maintain durability. The method of coating with glass is, for example, using a glass powder such as lead borosilicate glass as a slurry, and applying this slurry to the surface of the voltage dividing resistor by dipping, blade coating, spray coating, etc. It may be mentioned that the slurry is dried and then calcined.
【００１３】 本発明の温度センサでは、電流を抵抗体
に印加して電圧を検出してもよい。この場合、リード、
端子パッド等は、抵抗値がかなり高くても、温度を測定
する精度は維持できる。この場合、抵抗体に電流を印加
したときに発生する電圧を検出するための電圧検出リー
ドを有することが好ましい。この電圧検出リードは抵抗
体に電気的に接続する。一方、電圧を抵抗体に印加して
電流を検出してもよい。抵抗体、リード、端子パッド
は、セラミック基体に印刷塗布されることが好ましい。
しかし、ブレード塗布、スプレー塗布等されてもよい。In the temperature sensor of the present invention, current may be applied to the resistor to detect voltage. In this case, the lead,
Even if the resistance value of the terminal pad is considerably high, the accuracy of measuring the temperature can be maintained. In this case, it is preferable to have a voltage detection lead for detecting the voltage generated when a current is applied to the resistor. The voltage detection lead is electrically connected to the resistor. On the other hand, a voltage may be applied to the resistor to detect the current. The resistors, leads and terminal pads are preferably printed and applied to the ceramic substrate.
However, blade coating, spray coating or the like may be used.
【００１４】[0014]
【実施例】以下、本発明を実施例により詳細に説明す
る。ただし、本発明は下記実施例により制限されるもの
ではない。 （実施例１）本発明の一実施例の温度センサについて、
図面を参照しながら説明する。図１は、本発明の一実施
例の分解斜視図である。また、図１は、本発明の一実施
例を製造する過程における斜視図として把握することも
できる。セラミック基板１の表面に、白金とアルミナと
の混合ペーストから構成される抵抗体２が印刷付与され
る。図１において、セラミック基板１は、生素地のアル
ミナであって、焼成されていないものである。EXAMPLES The present invention will be described in detail below with reference to examples. However, the present invention is not limited to the following examples. (Example 1) Regarding the temperature sensor of one example of the present invention,
A description will be given with reference to the drawings. FIG. 1 is an exploded perspective view of an embodiment of the present invention. Further, FIG. 1 can be understood as a perspective view in the process of manufacturing an embodiment of the present invention. A resistor 2 made of a mixed paste of platinum and alumina is printed on the surface of the ceramic substrate 1. In FIG. 1, the ceramic substrate 1 is a green alumina, which is not fired.
【００１５】 セラミック基板１の表面には、抵抗体２
の両端に接続された電流リード３、４が印刷付与され
る。電流リード３、４の他方の端部には、セラミック基
板１の側面１ｓでの導通を確保するための接続パッド
７、８が設けられている。セラミック基板１の表面に
は、抵抗体２の両端に接続された電圧検出リード５、６
が印刷付与される。電圧検出リード５、６の他方の端部
には、セラミック基板１の側面１ｓでの導通を確保する
ための接続パッド９、１０が設けられている。なお、抵
抗体２の端部２ａは、電流リード３及び電圧検出リード
５に分枝し、抵抗体２の端部２ｂは、電流リード４及び
電圧検出リード６に分枝する。A resistor 2 is provided on the surface of the ceramic substrate 1.
The current leads 3 and 4 connected to both ends of are printed. Connection pads 7 and 8 are provided at the other ends of the current leads 3 and 4 for ensuring electrical continuity on the side surface 1s of the ceramic substrate 1. On the surface of the ceramic substrate 1, voltage detection leads 5 and 6 connected to both ends of the resistor 2 are formed.
Is printed. Connection pads 9 and 10 are provided at the other ends of the voltage detection leads 5 and 6 for ensuring electrical continuity on the side surface 1s of the ceramic substrate 1. The end 2a of the resistor 2 branches into the current lead 3 and the voltage detection lead 5, and the end 2b of the resistor 2 branches into the current lead 4 and the voltage detection lead 6.
【００１６】 電流リード３、４、電圧検出リード５、
６及び接続パッド７、８、９、１０は、例えば、白金と
アルミナとの混合ペーストで構成される。これらは、抵
抗体が印刷付与される工程で、同時に印刷付与されるこ
とが好ましい。しかし、電流リード３、４、電圧検出リ
ード５、６及び接続パッド７、８、９、１０の材料は、
抵抗体２と電気的に接続する限り、抵抗体２の材料と同
一性を有する必要はない。セラミック基板１１は、セラ
ミック基板１と同一の材料で構成されていることが好ま
しい。図１において、セラミック基板１１は、例えば、
生素地のアルミナである。セラミック基板１１の側面１
１ｓには、接続パッド７、８に電気的に接続するための
側面導通１２、１３が、印刷付与されている。The current leads 3 and 4, the voltage detection lead 5,
6 and the connection pads 7, 8, 9, and 10 are made of, for example, a mixed paste of platinum and alumina. These are preferably printed and applied at the same time in the step of printing and applying the resistor. However, the materials of the current leads 3, 4, the voltage detection leads 5, 6 and the connection pads 7, 8, 9, 10 are:
As long as it is electrically connected to the resistor 2, it does not have to have the same material as that of the resistor 2. The ceramic substrate 11 is preferably made of the same material as the ceramic substrate 1. In FIG. 1, the ceramic substrate 11 is, for example,
It is a green alumina. Side 1 of ceramic substrate 11
Side conductors 12, 13 for electrically connecting to the connection pads 7, 8 are printed on the 1s.
【００１７】 端子パッド１５は、側面導通１２に電気
的に接続する。また、側面導通１２、１３の間には、分
圧パッド１６が印刷付与される。分圧パッドは、側面導
通１２、１３のほぼ中央に配置してもよい。分圧パッド
１６は、端子パッド１７に接続する。端子パッド１５
と、端子パッド１７とは互いに交わらない。端子パッド
１５、１７及び分圧パッド１６は、セラミック基板１１
の端部１１ａの表面に印刷付与される。端子パッド１
５、１７及び分圧パッド１６は、例えば、例えば、白金
とアルミナとの混合ペーストで構成される。端子パッド
１５、１７及び分圧パッド１６の材料は、抵抗体２の材
料と同一性を有する必要はない。The terminal pad 15 is electrically connected to the side conduction 12. Further, a voltage dividing pad 16 is printed and provided between the side surfaces 12 and 13. The voltage dividing pad may be arranged substantially at the center of the side conductions 12, 13. The voltage dividing pad 16 is connected to the terminal pad 17. Terminal pad 15
And the terminal pad 17 do not intersect with each other. The terminal pads 15 and 17 and the voltage dividing pad 16 are the ceramic substrate 11
Is printed on the surface of the end portion 11a of the. Terminal pad 1
5, 17 and the voltage dividing pad 16 are made of, for example, a mixed paste of platinum and alumina. The material of the terminal pads 15, 17 and the voltage dividing pad 16 does not need to be the same as the material of the resistor 2.
【００１８】 セラミック基板１８は、セラミック基板
１と同一の材料で構成されていることが好ましい。図１
において、セラミック基板１８は、例えば、生素地のア
ルミナである。セラミック基板１８の側面１８ｓには、
接続パッド９、１０に電気的に接続するための側面導通
１９、２０が、アルミナ基板１８の裏面に延びるように
印刷付与されている。それぞれの側面導通１９、２０
は、アルミナ基板１８の裏面に印刷付与される端子パッ
ド２１、２２に接続する。側面導通１９、２０及び端子
パッド２１、２２は、例えば、白金とアルミナとの混合
ペーストで構成される。しかし、側面導通１９、２０及
び端子パッド２１、２２の材料は、抵抗体２の材料と同
一性を有する必要はない。The ceramic substrate 18 is preferably made of the same material as the ceramic substrate 1. Figure 1
In, the ceramic substrate 18 is, for example, green alumina. On the side surface 18s of the ceramic substrate 18,
Side surface conductions 19 and 20 for electrically connecting to the connection pads 9 and 10 are printed so as to extend to the back surface of the alumina substrate 18. Each side connection 19, 20
Is connected to the terminal pads 21 and 22 printed on the back surface of the alumina substrate 18. The side surface connections 19 and 20 and the terminal pads 21 and 22 are made of, for example, a mixed paste of platinum and alumina. However, the materials of the side-surface conductions 19, 20 and the terminal pads 21, 22 do not need to be the same as the material of the resistor 2.
【００１９】 これらの３つのセラミック基板１、１
１、１８を互いに積層して、圧着し、次いで、１６００
℃で焼成して一体化する。焼成するときの雰囲気は、抵
抗体２がタングステン、ニッケルのとき、還元雰囲気が
好ましく、抵抗体２が白金、ロジウム等のとき、還元雰
囲気でもよければ酸化雰囲気でもよい。側面導通１２、
１３を接続するため、酸化ルテニウムとガラスとの混合
体からなる分圧抵抗体１４が印刷焼き付けされる。この
分圧抵抗体１４は、分圧パッド１６の少なくとも一部を
被覆し、分圧パッドと電気的に接続する。These three ceramic substrates 1, 1
1, 18 laminated to each other, crimped, then 1600
Bake at ℃ to integrate. The atmosphere for firing is preferably a reducing atmosphere when the resistor 2 is tungsten or nickel, and may be a reducing atmosphere or an oxidizing atmosphere when the resistor 2 is platinum, rhodium or the like. Side conduction 12,
In order to connect 13, the voltage dividing resistor 14 made of a mixture of ruthenium oxide and glass is printed and printed. The voltage dividing resistor 14 covers at least a part of the voltage dividing pad 16 and is electrically connected to the voltage dividing pad.
【００２０】 次いで、抵抗体に端子パッド２１、２２
より所定の電流を流して、端子パッド１５、１７で電圧
を検出しながら、分圧抵抗体をレーザーでトリミング
し、検出する電圧が所定の値となるようにして、分圧抵
抗体の抵抗値を調整した。このとき印加する電流は、直
流でもよければ、交流でもよい。Then, the resistor is connected to the terminal pads 21 and 22.
The voltage dividing resistor is trimmed with a laser while a predetermined current is flown to detect the voltage at the terminal pads 15 and 17 so that the detected voltage has a predetermined value. Was adjusted. The current applied at this time may be direct current or alternating current.
【００２１】 次に、この温度センサ３０を自動車の排
気管３１に使用する態様を図２に例示する。温度センサ
３０は、ハウジング３２を介して、排気管３１に装着さ
れる。このとき、抵抗体２が埋設する端部３０ａが排気
管３１の内部に突出させ、分圧抵抗体１４を有する端部
３０ｂが排気管３１の外部になるように配置する。ハウ
ジング３２の内部には、温度センサ３０との緩衝部材３
３が設けられている。温度センサ３０の基体がセラミッ
クであって、衝撃に弱いため、端部３０ａは保護カバー
３４で覆われている。保護カバー３４には、複数個の貫
通孔を設けられ、排気ガスを保護カバー３４の内部に導
入できるようにする。Next, a mode in which the temperature sensor 30 is used for the exhaust pipe 31 of an automobile is illustrated in FIG. The temperature sensor 30 is attached to the exhaust pipe 31 via the housing 32. At this time, the end portion 30a in which the resistor 2 is embedded is projected inside the exhaust pipe 31, and the end portion 30b having the voltage dividing resistor 14 is arranged outside the exhaust pipe 31. Inside the housing 32, the buffer member 3 for the temperature sensor 30 is provided.
3 is provided. Since the base of the temperature sensor 30 is made of ceramic and is weak against impact, the end 30a is covered with the protective cover 34. The protective cover 34 is provided with a plurality of through holes so that exhaust gas can be introduced into the protective cover 34.
【００２２】 温度センサ３０の他方の端部３０ｂは、
コネクタ３６に接続し、端子パッド１５、１７、２１、
２２で検出する電気信号をコネクタ３６を介してライン
３７に伝えることができる。温度センサ３０の端部３０
ｂ及びコネクタ３６はケーシング３５に挿入されてい
る。The other end 30b of the temperature sensor 30 is
Connected to the connector 36, the terminal pads 15, 17, 21,
The electrical signal detected at 22 can be transmitted to the line 37 via the connector 36. End 30 of temperature sensor 30
b and the connector 36 are inserted in the casing 35.
【００２３】 上記実施例では、３つのセラミック基板
を積層圧着して、次いで、焼成することで一体化してセ
ラミック基体を形成する。しかし、３つのセラミック基
板が必須であるわけではない。例えば、セラミック基板
１８を省略し、セラミック基板１の裏面に、それぞれの
接続パッド９、１０に電気的に接続する端子パッドを印
刷付与してもよい。In the above embodiment, the three ceramic substrates are laminated and pressure-bonded and then fired to be integrated to form a ceramic substrate. However, three ceramic substrates are not essential. For example, the ceramic substrate 18 may be omitted, and terminal pads electrically connected to the respective connection pads 9 and 10 may be printed on the back surface of the ceramic substrate 1.
【００２４】 以下、抵抗体をセラミックス基体に埋設
させる他の手段を記載する。 （実施例２）生素地であって、抵抗体２、リードが設け
られている図１のセラミック基板１の表面に抵抗体２を
被覆して、リードの一部を被覆しないようにセラミック
ペーストを塗布し、これらを焼成して一体化する。図３
で、セラミック基板４１ａ及び被覆層４１ｂを有するセ
ラミック基体４１の内部に抵抗体４２が埋設する。被覆
層４１ｂに被覆されておらず、かつ、セラミック基板４
１ａの表面にあるリードの少なくとも一部を被覆するよ
うに分圧抵抗体を設け、この分圧抵抗体をガラスで更に
被覆する。Other means for embedding the resistor in the ceramic substrate will be described below. (Embodiment 2) The surface of the ceramic substrate 1 of FIG. 1 which is a green body and has the resistors 2 and leads is covered with the resistor 2, and a ceramic paste is applied so as not to cover a part of the leads. After coating, these are baked and integrated. Figure 3
Then, the resistor 42 is embedded inside the ceramic substrate 41 having the ceramic substrate 41a and the coating layer 41b. The ceramic substrate 4 not covered with the coating layer 41b
A voltage dividing resistor is provided so as to cover at least a part of the lead on the surface of 1a, and this voltage dividing resistor is further covered with glass.
【００２５】（実施例３）生素地のセラミック基板の表
面に、実施例１と同様に、抵抗体及びリードを印刷付与
し、抵抗体は、セラミック基板の一方の端部に配置す
る。セラミック基板のその端部をセラミックスラリー中
に浸漬させ、抵抗体を含有する端部をセラミックコート
層で被覆させ、次いで、焼成し、セラミック基板とセラ
ミックコート層とを一体化させることができる。図４
で、セラミック基板４６ａ及び被覆層４６ｂを有するセ
ラミック基体４６の内部に抵抗体４７が埋設する。被覆
層４６ｂに被覆されておらず、かつ、セラミック基板４
６ａの表面にあるリードの少なくとも一部を被覆するよ
うに分圧抵抗体を設け、この分圧抵抗体をガラスで更に
被覆する。(Embodiment 3) A resistor and a lead are printed on the surface of the ceramic substrate of the green body in the same manner as in Embodiment 1, and the resistor is arranged at one end of the ceramic substrate. The end of the ceramic substrate can be dipped in the ceramic slurry, the end containing the resistor can be coated with the ceramic coat layer, and then fired to integrate the ceramic substrate and the ceramic coat layer. Figure 4
Then, the resistor 47 is embedded inside the ceramic substrate 46 having the ceramic substrate 46a and the coating layer 46b. The ceramic substrate 4 not covered with the coating layer 46b
A voltage dividing resistor is provided so as to cover at least a part of the lead on the surface of 6a, and this voltage dividing resistor is further covered with glass.
【００２６】（実施例４）図５の温度センサ５０は、セ
ラミック基体５１の内部に抵抗体５２が埋設する。抵抗
体５２で温度を測定するときの熱が、分圧抵抗体５４に
伝導し難くするため、セラミック基体５１には、中空部
５８が設けられている。(Embodiment 4) In the temperature sensor 50 of FIG. 5, a resistor 52 is embedded inside a ceramic substrate 51. The ceramic base 51 is provided with a hollow portion 58 in order to make it difficult for the heat generated when the temperature is measured by the resistor 52 to be conducted to the voltage dividing resistor 54.
【００２７】（実施例５）図６の温度センサ６０は、セ
ラミック基体６１の内部に抵抗体６２が埋設する。抵抗
体６２で温度を測定するときの熱が、分圧抵抗体６４に
伝導し難くするため、セラミック基体６１の端部６１ａ
がそれ以外の部位より薄くなっている。(Embodiment 5) In the temperature sensor 60 of FIG. 6, a resistor 62 is embedded inside a ceramic base 61. The heat at the time of measuring the temperature with the resistor 62 is less likely to be conducted to the voltage dividing resistor 64.
Is thinner than other parts.
【００２８】[0028]
【発明の効果】 本発明の温度センサでは、抵抗体がセ
ラミック基体に埋没するので、抵抗体が劣化し難い。ま
た、分圧抵抗体の抵抗値を調整できるので、温度センサ
の抵抗値のバラツキが小さくなる。更に、分圧抵抗体の
抵抗値が、抵抗体の抵抗値より大きくすることで、温度
センサの精度を向上することができる。According to the temperature sensor of the present invention, the resistor is buried in the ceramic substrate, so that the resistor is less likely to deteriorate. Moreover, since the resistance value of the voltage dividing resistor can be adjusted, the variation in the resistance value of the temperature sensor is reduced. Furthermore, by setting the resistance value of the voltage dividing resistor to be larger than the resistance value of the resistor, the accuracy of the temperature sensor can be improved.
【図１】 本発明の温度センサの一実施例の分解斜視図
である。FIG. 1 is an exploded perspective view of an embodiment of a temperature sensor of the present invention.
【図２】 本発明の温度センサの使用態様を示す断面図
である。FIG. 2 is a cross-sectional view showing a usage mode of the temperature sensor of the present invention.
【図３】 本発明の温度センサの一実施例の断面説明図
である。FIG. 3 is a cross-sectional explanatory view of an embodiment of the temperature sensor of the present invention.
【図４】 本発明の温度センサの一実施例の断面説明図
である。FIG. 4 is a cross-sectional explanatory view of an embodiment of the temperature sensor of the present invention.
【図５】 本発明の温度センサの一実施例の斜視図であ
る。FIG. 5 is a perspective view of an embodiment of the temperature sensor of the present invention.
【図６】 本発明の温度センサの一実施例の斜視図であ
る。FIG. 6 is a perspective view of an embodiment of the temperature sensor of the present invention.
【図７】 図１の部分拡大図である。7 is a partially enlarged view of FIG.
１・・・セラミック基板、１ｓ・・・側面、２・・・抵抗体、３・
・・電流リード、４・・・電流リード、５・・・電圧検出リー
ド、６・・・電圧検出リード、７・・・接続パッド、８・・・接
続パッド、９・・・接続パッド、１０・・・接続パッド、１１
・・・セラミック基板、１１ｓ・・・側面、１２・・・側面導
通、１３・・・側面導通、１４・・・分圧抵抗体、１５・・・端
子パッド、１６・・・分圧パッド、１７・・・端子パッド、１
８・・・セラミック基板、１８ｓ・・・側面、１９・・・側面導
通、２０・・・側面導通、２１・・・端子パッド、２２・・・端
子パッド、３０・・・温度センサ、３１・・・排気管、３２・・
・ハウジング、３３・・・緩衝部材、３４・・・保護カバー、
３５・・・ケーシング、３６・・・コネクタ、３７・・・ライ
ン、４１・・・セラミック基体、４１ａ・・・セラミック基
板、４１ｂ・・・被覆層、４２・・・抵抗体、４６・・・セラミ
ック基体、４６ａ・・・セラミック基板、４６ｂ・・・被覆
層、４７・・・抵抗体、５０・・・温度センサ、５１・・・セラ
ミック基体、５２・・・抵抗体、５３・・・側面導通、５４・・
・分圧抵抗体、５５・・・端子パッド、５６・・・分圧パッ
ド、５７・・・端子パッド、５８・・・中空部、６０・・・温度
センサ、６１・・・セラミック基体、６１ａ・・・端部、６２
・・・抵抗体、６３・・・側面導通、６４・・・分圧抵抗体、６
６・・・端子パッド、６６・・・分圧パッド、６７・・・端子パ
ッド1 ... Ceramic substrate, 1s ... Side surface, 2 ... Resistor, 3 ...
..Current leads, 4 ... Current leads, 5 ... Voltage detection leads, 6 ... Voltage detection leads, 7 ... Connection pads, 8 ... Connection pads, 9 ... Connection pads, 10 ... Connecting pads, 11
... Ceramic substrate, 11s ... Side surface, 12 ... Side conduction, 13 ... Side conduction, 14 ... Voltage dividing resistor, 15 ... Terminal pad, 16 ... Voltage dividing pad, 17 ... Terminal pads, 1
8 ... Ceramic substrate, 18s ... Side surface, 19 ... Side conduction, 20 ... Side conduction, 21 ... Terminal pad, 22 ... Terminal pad, 30 ... Temperature sensor, 31 ... ..Exhaust pipes, 32 ...
・ Housing, 33 ... Buffer member, 34 ... Protective cover,
35 ... Casing, 36 ... Connector, 37 ... Line, 41 ... Ceramic base, 41a ... Ceramic substrate, 41b ... Coating layer, 42 ... Resistor, 46 ... Ceramic substrate, 46a ... Ceramic substrate, 46b ... Coating layer, 47 ... Resistor, 50 ... Temperature sensor, 51 ... Ceramic substrate, 52 ... Resistor, 53 ... Side surface Continuity, 54 ...
・ Voltage-dividing resistor, 55 ... Terminal pad, 56 ... Voltage-dividing pad, 57 ... Terminal pad, 58 ... Hollow part, 60 ... Temperature sensor, 61 ... Ceramic base, 61a ... Ends, 62
... Resistors, 63 ... Lateral conduction, 64 ... Voltage dividing resistors, 6
6 ... Terminal pads, 66 ... Voltage dividing pads, 67 ... Terminal pads
【手続補正書】[Procedure amendment]
【提出日】平成６年４月２８日[Submission date] April 28, 1994
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００７[Correction target item name] 0007
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００７】 セラミック基体に用いるセラミックは、
抵抗体の抵抗値と比較して、電気的に絶縁性であること
が好ましい。また、熱伝導率が小さい方が、温度センサ
の精度を高めるので好ましい。セラミック基体は、例え
ば、アルミナ、ステアタイト、ムライト等を用いること
ができる。セラミック基体は、全体が同一の材料からな
ることが好ましいが、セラミック基体のある部分が他の
部分と異なる材料であってもよい。また、セラミック基
体は、ガス分子が透過しないように、緻密であることが
好ましい。セラミック基体の形状は、板状に限らず、棒
状、パイプ状であってもよい。この形状は、抵抗体で測
定する温度が、分圧抵抗体に影響を及ぼし難い形状、即
ち、熱伝導率が小さくなるような形状が好ましい。The ceramic used for the ceramic substrate is
It is preferably electrically insulating as compared with the resistance value of the resistor. In addition, it is preferable that the thermal conductivity is small because the accuracy of the temperature sensor is improved. As the ceramic substrate, for example, alumina, steatite, mullite or the like can be used. The ceramic substrate is preferably made of the same material as a whole, but one portion of the ceramic substrate may be made of a material different from that of another portion. Further, the ceramic substrate is preferably dense so that gas molecules do not pass through. The shape of the ceramic substrate is not limited to the plate shape, and may be a rod shape or a pipe shape. This shape is preferably a shape in which the temperature measured by the resistor does not easily affect the voltage dividing resistor, that is, a shape in which the thermal conductivity is small.
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００９[Correction target item name] 0009
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００９】 分圧抵抗体は、抵抗体に電気的に接続す
るものであり、例えば、電流リードを介して抵抗体に接
続する。分圧抵抗体は、抵抗体と異なって、抵抗温度係
数が小さいことが好ましい。分圧抵抗体は、例えば、金
属又は金属酸化物がセラミック基体に印刷付与されたも
の、金属又は金属酸化物の粒子がガラスに分散したも
の、金属又は金属酸化物からなる薄膜、金属細線等を用
いることができる。分圧抵抗体は、セラミック基体の表
面の少なくとも一部を被覆することが好ましく、これに
より、分圧抵抗体をレーザー等でトリミングすることが
でき、電流印加時の抵抗体からの出力電圧を調整するこ
とができる。即ち、所定温度（例えば、２５℃）で、抵
抗体に所定の電流を流したときに発生する逆起電力を、
出力電圧として検出しながら、分圧抵抗体をレーザーで
トリミングすることで、分圧抵抗体の抵抗値を調整する
ことができる。従って、個々の温度センサにおける抵抗
体での出力電圧のバラツキが低減される。The voltage dividing resistor is electrically connected to the resistor, and is connected to the resistor via a current lead, for example. Unlike the resistor, the voltage dividing resistor preferably has a small temperature coefficient of resistance. The voltage dividing resistor may be, for example, one in which a metal or a metal oxide is printed on a ceramic substrate, one in which particles of a metal or a metal oxide are dispersed in glass, a thin film made of a metal or a metal oxide, a fine metal wire, or the like. Can be used. The voltage dividing resistor preferably covers at least a part of the surface of the ceramic substrate, whereby the voltage dividing resistor can be trimmed with a laser or the like, and the output voltage from the resistor at the time of applying a current is adjusted. can do. That is, the counter electromotive force generated when a predetermined current is passed through the resistor at a predetermined temperature (for example, 25 ° C.) is
The resistance value of the voltage dividing resistor can be adjusted by trimming the voltage dividing resistor with a laser while detecting it as the output voltage . Therefore, the resistance of the individual temperature sensors
The variation of the output voltage in the body is reduced.
【手続補正３】[Procedure 3]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１０[Correction target item name] 0010
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１０】 また、分圧抵抗体は、抵抗体よりも抵抗
温度係数が小さいので、レーザで分圧抵抗体をトリミン
グすることを、レーザーで抵抗体をトリミングすること
と比較すると、レーザー照射を受ける分圧抵抗体に発生
する熱に起因する分圧抵抗体の抵抗値の誤差が小さくな
る。更にまた、分圧抵抗体は、温度を測定する雰囲気に
は接触しない部位に配置できるので、分圧抵抗体が劣化
し難くなり、分圧抵抗体は抵抗値が経時変化し難い。Further, since the voltage dividing resistor has a smaller temperature coefficient of resistance than the resistor, trimming the voltage dividing resistor with a laser is irradiated with laser as compared with trimming the resistor with a laser. The error in the resistance value of the voltage dividing resistor due to the heat generated in the voltage dividing resistor is reduced. Furthermore, since the voltage dividing resistor can be arranged in a portion that does not come into contact with the atmosphere for measuring the temperature, the voltage dividing resistor is less likely to deteriorate, and the resistance value of the voltage dividing resistor is less likely to change with time.
【手続補正４】[Procedure amendment 4]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１５[Name of item to be corrected] 0015
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１５】 セラミック基板１の表面には、抵抗体２
の両端に接続された電流リード３、４が印刷付与され
る。電流リード３、４の他方の端部には、セラミック基
板１の側面１ｓでの導通を確保するための接続パッド
９、１０が設けられている。セラミック基板１の表面に
は、抵抗体２の両端に接続された電圧検出リード５、６
が印刷付与される。電圧検出リード５、６の他方の端部
には、セラミック基板１の側面１ｓでの導通を確保する
ための接続パッド７、８が設けられている。なお、抵抗
体２の端部２ａは、電流リード３及び電圧検出リード５
に分枝し、抵抗体２の端部２ｂは、電流リード４及び電
圧検出リード６に分枝する。A resistor 2 is provided on the surface of the ceramic substrate 1.
The current leads 3 and 4 connected to both ends of are printed. At the other end of the current leads 3 and 4, connection pads for ensuring continuity on the side surface 1s of the ceramic substrate 1 are provided.
9 and 10 are provided. On the surface of the ceramic substrate 1, voltage detection leads 5 and 6 connected to both ends of the resistor 2 are formed.
Is printed. Connection pads 7 and 8 are provided at the other ends of the voltage detection leads 5 and 6 for ensuring electrical continuity on the side surface 1s of the ceramic substrate 1. The end 2a of the resistor 2 has a current lead 3 and a voltage detection lead 5
The end portion 2b of the resistor 2 branches to the current lead 4 and the voltage detection lead 6.
【手続補正５】[Procedure Amendment 5]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１７[Correction target item name] 0017
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１７】 端子パッド１５は、側面導通１２に電気
的に接続する。また、側面導通１２、１３の間には、分
圧パッド１６が印刷付与される。分圧パッドは、側面導
通１２、１３のほぼ中央に配置してもよい。分圧パッド
１６は、端子パッド１７に接続する。端子パッド１５
と、端子パッド１７とは互いに交わらない。端子パッド
１５、１７及び分圧パッド１６は、セラミック基板１１
の端部１１ａの表面に印刷付与される。端子パッド１
５、１７及び分圧パッド１６は、例えば、白金とアルミ
ナとの混合ペーストで構成される。端子パッド１５、１
７及び分圧パッド１６の材料は、抵抗体２の材料と同一
性を有する必要はない。The terminal pad 15 is electrically connected to the side conduction 12. Further, a voltage dividing pad 16 is printed and provided between the side surfaces 12 and 13. The voltage dividing pad may be arranged substantially at the center of the side conductions 12, 13. The voltage dividing pad 16 is connected to the terminal pad 17. Terminal pad 15
And the terminal pad 17 do not intersect with each other. The terminal pads 15 and 17 and the voltage dividing pad 16 are the ceramic substrate 11
Is printed on the surface of the end portion 11a of the. Terminal pad 1
5, 17 and the voltage dividing pad 16 are made of, for example , a mixed paste of platinum and alumina. Terminal pads 15, 1
The material of 7 and voltage divider pad 16 need not be identical to the material of resistor 2.
【手続補正６】[Procedure correction 6]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００２１[Correction target item name] 0021
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００２１】 次に、この温度センサ３０を自動車の排
気管３１に使用する態様を図２に例示する。温度センサ
３０は、ハウジング３２を介して、排気管３１に装着さ
れる。このとき、抵抗体２が埋設する端部３０ａが排気
管３１の内部に突出させ、分圧抵抗体１４を有する端部
３０ｂが排気管３１の外部になるように配置する。ハウ
ジング３２の内部には、温度センサ３０との緩衝部材３
３が設けられている。温度センサ３０の基体がセラミッ
クであって、衝撃に弱いため、端部３０ａは保護カバー
３４で覆われている。保護カバー３４には、複数個の貫
通孔が設けられ、排気ガスを保護カバー３４の内部に導
入できるようにする。 ─────────────────────────────────────────────────────
Next, a mode in which the temperature sensor 30 is used for the exhaust pipe 31 of an automobile is illustrated in FIG. The temperature sensor 30 is attached to the exhaust pipe 31 via the housing 32. At this time, the end portion 30a in which the resistor 2 is embedded is projected inside the exhaust pipe 31, and the end portion 30b having the voltage dividing resistor 14 is arranged outside the exhaust pipe 31. Inside the housing 32, the buffer member 3 for the temperature sensor 30 is provided.
3 is provided. Since the base of the temperature sensor 30 is made of ceramic and is weak against impact, the end 30a is covered with the protective cover 34. The protective cover 34 is provided with a plurality of through holes so that exhaust gas can be introduced into the protective cover 34. ─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成７年２月２７日[Submission date] February 27, 1995
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００９[Correction target item name] 0009
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００９】 分圧抵抗体は、抵抗体に電気的に接続す
るものであり、電圧リードを介して抵抗体に接続する。
分圧抵抗体は、抵抗体と異なって、抵抗温度係数が小さ
いことが好ましい。分圧抵抗体は、例えば、金属又は金
属酸化物がセラミック基体に印刷付与されたもの、金属
又は金属酸化物の粒子がガラスに分散したもの、金属又
は金属酸化物からなる薄膜、金属細線等を用いることが
できる。分圧抵抗体は、セラミック基体の表面の少なく
とも一部を被覆することが好ましく、これにより、分圧
抵抗体をレーザー等でトリミングすることができ、電流
印加時の抵抗体からの出力電圧を調整することができ
る。即ち、所定温度（例えば、２５℃）で、抵抗体に所
定の電流を流したときに発生する逆起電力を、出力電圧
として検出しながら、分圧抵抗体をレーザーでトリミン
グすることで、分圧抵抗体の抵抗値を調整することがで
きる。従って、個々の温度センサにおける抵抗体での出
力電圧のバラツキが低減される。The voltage dividing resistor is electrically connected to the resistor, and is connected to the resistor via a voltage lead.
Unlike the resistor, the voltage dividing resistor preferably has a small temperature coefficient of resistance. The voltage dividing resistor may be, for example, one in which a metal or a metal oxide is printed on a ceramic substrate, one in which particles of a metal or a metal oxide are dispersed in glass, a thin film made of a metal or a metal oxide, a fine metal wire, or the like. Can be used. The voltage dividing resistor preferably covers at least a part of the surface of the ceramic substrate, whereby the voltage dividing resistor can be trimmed with a laser or the like, and the output voltage from the resistor at the time of applying a current is adjusted. can do. That is, by detecting the counter electromotive force generated when a predetermined current is applied to the resistor at a predetermined temperature (for example, 25 ° C.) as the output voltage, the voltage dividing resistor is trimmed with a laser to divide the voltage. The resistance value of the piezoresistor can be adjusted. Therefore, variations in the output voltage of the resistors in the individual temperature sensors are reduced.
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１３[Correction target item name] 0013
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１３】 本発明の温度センサでは、電流を抵抗体
に印加して電圧を検出する。この場合、リード、端子パ
ッド等は、抵抗値がかなり高くても、温度を測定する精
度は維持できる。この場合、抵抗体に電流を印加したと
きに発生する電圧を検出するための電圧検出リードを有
する。この電圧検出リードは抵抗体に電気的に接続す
る。抵抗体、リード、端子パッドは、セラミック基体に
印刷塗布されることが好ましい。しかし、ブレード塗
布、スプレー塗布等されてもよい。In the temperature sensor of the present invention, the current is applied to the resistor to detect the voltage. In this case, the lead, the terminal pad, etc. can maintain the accuracy of measuring the temperature even if the resistance value is considerably high. In this case, there is a voltage detection lead for detecting the voltage generated when a current is applied to the resistor.
To do . The voltage detection lead is electrically connected to the resistor. The resistors, leads and terminal pads are preferably printed and applied to the ceramic substrate. However, blade coating, spray coating or the like may be used.
【手続補正３】[Procedure 3]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００２８[Correction target item name] 0028
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００２８】[0028]
【発明の効果】 本発明の温度センサでは、抵抗体がセ
ラミック基体に埋没するので、抵抗体が劣化し難い。ま
た、分圧抵抗体の抵抗値を調整できるので、温度センサ
の出力電圧のバラツキが小さくなる。更に、分圧抵抗体
の抵抗値を、抵抗体の抵抗値より大きくすることで、温
度センサの精度を向上することができる。According to the temperature sensor of the present invention, the resistor is buried in the ceramic substrate, so that the resistor is less likely to deteriorate. Further, since the resistance value of the voltage dividing resistor can be adjusted, variations in the output voltage of the temperature sensor are reduced. Furthermore, the accuracy of the temperature sensor can be improved by making the resistance value of the voltage dividing resistor larger than the resistance value of the resistor.
【手続補正４】[Procedure amendment 4]
【補正対象書類名】図面[Document name to be corrected] Drawing
【補正対象項目名】図２[Name of item to be corrected] Figure 2
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【図２】 [Fig. 2]
Claims (1)
埋没され、かつ、正の抵抗温度係数を有する抵抗体と、
該抵抗体に電流を印加するための電流リードと、該抵抗
体の電圧を検出するための電圧リードと、該電圧リード
間に発生する電圧を分圧する分圧抵抗体とを有し、該抵
抗体が、金属、合金、又は、金属とセラミックとの混合
物から構成されており、かつ、該抵抗体に所定の電流を
流した際に発生する電圧が所定電圧値となるように該分
圧抵抗体がトリミング調整されていることを特徴とする
温度センサ。1. A ceramic substrate, and a resistor embedded in the ceramic substrate and having a positive temperature coefficient of resistance,
The resistor has a current lead for applying a current to the resistor, a voltage lead for detecting the voltage of the resistor, and a voltage dividing resistor for dividing the voltage generated between the voltage leads. The body is made of a metal, an alloy, or a mixture of a metal and a ceramic, and the voltage dividing resistance is adjusted so that the voltage generated when a predetermined current is applied to the resistor has a predetermined voltage value. A temperature sensor whose body is trimmed.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32930693A JP3175890B2 (en) | 1993-12-27 | 1993-12-27 | Temperature sensor |
| DE4445243A DE4445243C2 (en) | 1993-12-27 | 1994-12-19 | temperature sensor |
| GB9425779A GB2285138B (en) | 1993-12-27 | 1994-12-21 | Temperature sensor |
| US08/815,431 US5823680A (en) | 1993-12-27 | 1997-03-11 | Temperature sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32930693A JP3175890B2 (en) | 1993-12-27 | 1993-12-27 | Temperature sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07190863A true JPH07190863A (en) | 1995-07-28 |
| JP3175890B2 JP3175890B2 (en) | 2001-06-11 |
Family
ID=18219992
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP32930693A Expired - Lifetime JP3175890B2 (en) | 1993-12-27 | 1993-12-27 | Temperature sensor |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US5823680A (en) |
| JP (1) | JP3175890B2 (en) |
| DE (1) | DE4445243C2 (en) |
| GB (1) | GB2285138B (en) |
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| US5041809A (en) * | 1990-01-08 | 1991-08-20 | General Electric Company | Glass-ceramic temperature sensor for heating ovens |
| US5053740A (en) * | 1990-01-11 | 1991-10-01 | General Electric Company | Porcelain enamel temperature sensor for heating ovens |
| DE4007129A1 (en) * | 1990-03-07 | 1991-09-12 | Fraunhofer Ges Forschung | TEMPERATURE SENSOR |
| EP0461102A3 (en) * | 1990-06-05 | 1992-08-12 | Austria Email-Eht Aktiengesellschaft | Temperature sensitive sensor |
| JPH0833327B2 (en) * | 1990-06-11 | 1996-03-29 | 株式会社村田製作所 | Temperature sensor |
| DE4025715C1 (en) * | 1990-08-14 | 1992-04-02 | Robert Bosch Gmbh, 7000 Stuttgart, De | |
| DE4026061C1 (en) * | 1990-08-17 | 1992-02-13 | Heraeus Sensor Gmbh, 6450 Hanau, De | |
| EP0571412B1 (en) * | 1991-02-15 | 1998-05-27 | Siemens Aktiengesellschaft | High temperature sensor made of metal of the platinum group |
| JPH04279831A (en) * | 1991-03-08 | 1992-10-05 | Matsushita Electric Ind Co Ltd | Platinum temperature sensor |
| JP3203803B2 (en) * | 1992-09-01 | 2001-08-27 | 株式会社デンソー | Thermistor type temperature sensor |
-
1993
- 1993-12-27 JP JP32930693A patent/JP3175890B2/en not_active Expired - Lifetime
-
1994
- 1994-12-19 DE DE4445243A patent/DE4445243C2/en not_active Expired - Lifetime
- 1994-12-21 GB GB9425779A patent/GB2285138B/en not_active Expired - Fee Related
-
1997
- 1997-03-11 US US08/815,431 patent/US5823680A/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6140906A (en) * | 1996-11-08 | 2000-10-31 | Tdk Corporation | Resistive temperature sensor and manufacturing method therefor |
| US6766574B2 (en) | 2000-05-24 | 2004-07-27 | Ngk Spark Plug Co., Ltd. | Production control method for temperature sensor by adjusting thickness of a heat-sensing surface side ceramic layer |
| JP2004511763A (en) * | 2000-10-07 | 2004-04-15 | ドクトル・ヨハネス・ハイデンハイン・ゲゼルシヤフト・ミツト・ベシユレンクテル・ハフツング | Device for detecting longitudinal expansion of mechanical parts due to heat |
| JP2006527378A (en) * | 2003-06-13 | 2006-11-30 | セラマスピード・リミテッド | Temperature detector for electric heating equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9425779D0 (en) | 1995-02-22 |
| JP3175890B2 (en) | 2001-06-11 |
| GB2285138A (en) | 1995-06-28 |
| DE4445243A1 (en) | 1995-06-29 |
| US5823680A (en) | 1998-10-20 |
| GB2285138B (en) | 1997-10-22 |
| DE4445243C2 (en) | 2002-03-21 |
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